OPERATING INSTRUCTIONS
M68HC11EVB/D
4-1
1
CHAPTER 4
OPERATING INSTRUCTIONS
4.1 INTRODUCTION
This chapter provides the necessary information to initialize and operate the EVB in a target
system environment. Information consists of the control switch description, operating limitations,
command line format, monitor commands, and operating procedures. The operating procedures
consist of assembly/disassembly and downloading descriptions and examples.
4.2 CONTROL SWITCH
The EVB contains a user reset switch S1. This switch is a momentary action push-button switch
that resets the EVB MCU circuits.
4.3 LIMITATIONS
CAUTION
Caution should be observed when programming or erasing MCU
EEPROM locations. EVB MCU configuration (CONFIG) register
ROMON bit is cleared to disable MCU internal ROM, thereby
allowing external EPROM containing the BUFFALO program to
control EVB operations.
The MC68HC11 MCU SCI has been set for 9600 baud using a 2 MHz E clock external bus. This
baud rate can be changed by software by reprogramming the BAUD register in the ONSCI
subroutine of the BUFFALO monitor program. Refer to the buf25.asm file on the EVB diskettes
for additional information pertaining to the ONSCI subroutine.
As the RS-232C handshake lines are not used, a delay of approximately 300 milliseconds is
present between successive characters sent to the host computer during the execution of the
LOAD command in the monitor program.
The monitor program uses the MCU internal RAM located at $0048-$00FF. The control registers
are located at $1000-$103F. The monitor program also uses Output Compare 5 (OC5) for the
TRACE instruction, therefore OC5 should not be used in user routines being traced.
Summary of Contents for M68HC11EVB
Page 9: ...CONTENTS x M68HC11EVB D ...
Page 35: ...MONITOR PROGRAM 3 8 M68HC11EVB D ...
Page 81: ...OPERATING INSTRUCTIONS 4 46 M68HC11EVB D ...
Page 97: ...SUPPORT INFORMATION 6 12 M68HC11EVB D Figure 6 3 EVB Schematic Diagram Sheet 2 of 2 ...
Page 103: ...APPLICATIONS B 2 M68HC11EVB D Figure B 1 Single Chip Mode Configuration ...